WASHINGTON — The federal officials who partied too hard in Las Vegas will now suffer the hangover on Capitol Hill, as lawmakers compete to out-investigate one another.

A scandal that's also a political opportunity, the recent revelations about the absurdly lavish General Services Administration conference give congressional panel chairmen a big target. The serious shooting starts Monday.

"We've seen there's a problem, and we're going to be digging more deeply into this," Rep. Jeff Denham, R-Calif., said Friday.

Denham leads a House panel that oversees federal buildings, a post that previously garnered the freshman attention with scrutiny of a wasteful Securities and Exchange Commission lease. Those earlier hearings helped drive the SEC to cancel the lease.

Denham's House Subcommittee on Economic Development, Public Buildings and Emergency Management will hold a hearing Tuesday on the GSA's Las Vegas conference. That will be preceded Monday by a kickoff hearing with the House Committee on Oversight and Government Reform.

As revealed by an inspector general audit issued April 2, the General Services Administration spent $822,751 on its October 2010 Western Regional Conference. The total costs included six pre-conference planning trips by officials checking out the M Resort Spa Casino on the south end of the Las Vegas Strip.

The conference was attended by about 300 employees of the GSA, which manages federal buildings and operates as the administrative arm of the federal government.

Auditors called the conference spending "excessive, wasteful and in some cases impermissible." It included glittering hospitality suites, commemorative coins, breakfasts costing $44.80 a person and a $75,000 "team-building exercise" in which participants built bicycles from scratch.

"We want to be sure we hold accountable those who have misused public dollars," Denham said.

Acknowledging the spending was "very troubling" and "especially egregious," GSA Administrator Martha Johnson immediately resigned upon release of the inspector general's audit. Also, two deputies were fired and four managers were placed on leave. Congressional denunciations followed quickly.

Republican Rep. Darrell Issa, R-Calif., maneuvered his way to the head of the line by scheduling a leadoff hearing Monday before his House Oversight and Government Reform Committee. Although the back-to-back hearings could prove complementary and could amplify a Republican message about waste in the Obama administration, seizing the first spot gives Issa potentially higher visibility.

"We have failed to do our job of keeping after this ever-growing bureaucracy, which is our responsibility," Issa told the Fox News Channel's Greta Van Sustern earlier this month. "We shouldn't fund and then forget."

Issa has used his committee to go after the Obama administration on a variety of fronts, including loan guarantees for troubled solar energy firms. Playing defense, committee Democrats have hoped to extend the panel's inquiry into GSA problems during the Bush administration.

The GSA's 2008 conference in New Orleans during the Bush administration cost $655,000, agency records show.

"We're committed to doing all we can to make the situation right," Acting GSA Administrator Dan Tangherlini said April 10 on a video posted on the agency's website. "We've identified ways to be more efficient and effective stewards of taxpayer dollars."

Yet another House panel, the House Energy and Commerce Committee, has been obtaining and releasing Obama administration documents concerning travel by GSA officials.

In the Senate, Missouri Democratic Sen. Claire McCaskill has sharply questioned whether bonuses were improperly paid to GSA workers. She has not yet called for her own hearings into the Las Vegas conference, though she could do so eventually as chair of the Senate Subcommittee on Contracting Oversight.